Adjustable actuating lever



M y 9 w. F. DEHN 2,836,081

ADJUSTABLE ACTUATING LEVER Filed Sept. 8, 1955 2 Sheets-Sheet l G 4e 22 5 32 E 28 INVENTOR WILLIAM F. DEHN I BY W H W ATTORNEY May 27, 1958 w. F. DEHN 2,836,081

ADJUSTABLE ACTUATING LEVER Filed Sept. 8, 1955 2 Sheets-Sheet 2 nlnnnunluunnnuuunlu nmMunuuuq nnllnnmm IHHIHIEHHIHHIHIIMIIIMHHIBIHHI} \llnalnuumn INVENTOR WILLIAM F. DEHN ATTORNEY United States Patent C) 2,83 6,081 ADJUSTABLE ACTUATING LEVER Application September 8, 1955, Serial No. 533,072 4 Claims. (Cl. 74522) This invention relates to an adjustable actuating lever mechanism for rotatable control shafts, such as the control shaft for electrical limit switches; and resides more specifically in such a mechanism including an arm, a contact roller journaled on the outer end of the arm, and a clamp for clamping the arm to the control shaft with means permitting reversal of the arm end-for-end and face-for-face, and permitting angular adjustment between the clamp and the shaft, and permitting radial adjustment between the arm and the clamp, the radial adjustment being retained by cooperating ridges and indentations on clamp and arm which serve the additional function of indicating the effective length of the arm, and the angular adjustment being facilitated by means for steadying the shaft against rotation during such adjustment.

Although designed primarily for use with, and although shown in use with, a rotary limit-switch, the invention is applicable to other types of devices actuable by a rotatable shaft.

Devices of the general class to which the present invention is adapted, especially in the case of limit-switches, employ actuating levers of many different effective radial lengths, and of different axial location of the actuating roller carried by the lever, these differences being due to the requirements of the machines which the switches are designed to control. This necessitates the stocking of large numbers. of alternative levers. Also frequently a slight, or even major, adjustment of throw becomes necessary in the course of building the controlled machine, and this requires either sending to the manufacturer for another lever, or altering the machine. Accordingly, the principal object of the present invention is to provide an actuating lever which can be adjusted and firmly held, with the actuating roller in any one of a plurality of radial and axial positions.

Actuating levers of the general class to which the present invention is adapted can be secured to the control shaft in an infinity of angular positions. But the fineness of angular adjustment is interfered with by the fact that the shaft of such switches must be effortlessly rotatable. Accordingly, a further object of the present invention is to provide simple means for steadying the shaft during adjustment and during clamping the lever arm in adjusted position, and more specifically to design this means as compactly as possible.

A still further object of this invention is to provide a lever arm having a greater range of radial adjustment consistent with compactness.

A still further object is to provide that certain cooperating features of the clamping means and the lever arm shall perform the dual functions of clamping and of serving as index and scale to indicate the effective length of the adjusted arm.

- A still further object is to generally improve the rigidity and simplicity of the mechanism.

' These and other objects and advantages of the present invention are readily evident from the foregoing general 2,836,081 Patented May 27, 1953 description and/or will appear from the description to follow.

In the following description, accompanying drawings, which constitute a part of this specification, and in which there is shown, by way of illustration but not of limitation, a specific form in which the invention may be embodied.

In the drawings:

Fig. 1 is an actual size diagonal front perspective showing of a switch with the present invention attached.

Fig. 2 is a similar perspective showing of the operating head and part of the contact base of such a switch with the actuating lever and associated parts removed.

All the remaining figures are double-size.

Fig. 3 is a front elevation of the block.

Fig. 4 is a rear elevation of the same.

Fig. 5 is a view of the same from beneath, viewed from the line 5--5 of Fig. 3 or Fig. 4.

Fig. 6 is a side view of the same, line 6-6 of Figs. 3 and 6.

Fig. 7 is a front elevation of the actuating lever.

Fig. 8 is a rear elevation of the same.

Fig. 9 is a front elevation of the set screw which secures the block to the shaft, seen in the position which it occupies in Fig. 1.

Fig. 10 is a rear elevation of the plate.

Fig. 11 is a side elevation of the plate, viewed from the line 1111 of Fig. 10. I

Fig. 12 is a side elevation of the Allen-head screw which clamps the lever between the block and the plate.

Throughout the description, the same reference number is applied to the same member or to similar members.

Referring now to the drawings, more particularly to Figs. 1 and 2, it will be seen that 21 is the contact base of a limit switch (1. e., the switch proper), and 22 is the operating head thereof. None of the internal details of these two assemblages is shown, inasmuch as such details are immaterial to the present invention. In fact, it is not necessary that the switch be a limit switch, although the present invention is primarily adapted for use with such a switch, it being suificient that the switch be controllable by a rotatable shaft.

On the front face of operating head 22 is shown a bearing 23, which is immaterial to the present invention, and through which protrudes the control shaft 24. On the protruding end of shaft 24, there is a screw-head slot 25, the object of which will be hereinafter described.

A block 26 is removably secured rigidly to the protrading end of shaft 24 in any appropriate manner, such as the following. In a transverse hole 27 (see Fig. 6) is inserted set-screw 28 (see Fig. 9), which has a cutaway portion 29 and a threaded end 30. The cut-awayportion registers with hole 31 in block 26 (see Figs. 3 and 4), and the threaded portion protrudes from transverse hole 27. With the cut-away portion thus registering, the end of shaft 24 is inserted in hole 31, and a nut 32 is screwed onto threaded portion 30. The tightening of this nut forces cut-away portion 29 of set-screw 28 slightly out of register with hole 31, thus locking block 26 securely against either sliding off shaft 24 or rotating with respect to shaft 24.

inasmuch as shaft 24 is very readily rotatable, it isnecessary that some means he provided to keep it from rotating while block 26 is being secured thereto. Otherwise block 26 and the actuating contact arm (to be hereinafter described) could notbe finely securedin angular relation to the shaft. This holding means should be preferably some tool-engaging means, such as an Allen-head, knurled or polygonal sides, or (as shown) a screw-head indentation 25, capable of being engaged and held by a screwdriver. This screw-headindentationreference is made to the viewed from the 26, there are I tightening means, such as in Fig. l;

'cordin gly,

ing 52, to engage the of the distance of roller 42 from a lesser length of arm 33 than would otherwise be vals.

is preferred, as -ta-king up less space than the other alternatives.

The outer face of block-26' isdesigned to hold in radial adjustability' an actuating contact arm 33 (see Fig; 1).. These featnres-areshown in Figs. 3 and 5, 'Wherein outer ridges 34, and interrupted inner'ridgc 1 35%{3Ql0getli6f COIiSil-fllt parallel guide means for arm 33. 1'Eachbuter ridge'andxone side of the interrupted 7 inner ridge define between them a groove 37 in which may slide oneof -the two parallel-branches 33, into which farm 33 is bifurcated. i

V Onione face 'at the opposite end of arm .33 from bridge 39,-there' is journaled, as at 43,

an actuating contact roller 42, for the purpose of being engaged by a moving piece of. machinery (not shown) to actuate the switch, in manner well known in the art.

Transversely in the bottom of grooves 37 of block cooperating ridges 43, spaced so as to engage indentations40 of arm 33.

Finally, there is a clamp-plate 44 overlying the face of block 26, and clampable thereto, with arm 33 between them, by rneansof screw 45, which is inserted through asher 46, hole 47 in Clamp-plate, and threaded hole in block 26. The head 4? of screw 45 is provided with Allen-head screw 5%, as shown Clamp-plate. (see Figs'. and' 11) is provided withcooperating transverse ridges 51, spaced soas to engageindentations of arm 33. It will be noted that these'ridges Slare located at the extreme upper and lower edges of plate 44; also that the lower'edge of plate 44 is'exactly-aligned with the center of shaft 24. Acthese edges perform the function of indexes for reading the graduations on arm 33. in this connection projecting end of shaft 24 (see Fig. 1). This opening serves the additional function of steadying the plate against rotating about screw 45, and screw stcadies the plate against rotating about shaft 24.

Attention is also invited to the marking and accompanying arrows, engraved on each face of arm 33, as shown in Figs. 7. and '8; and to the fact that the arm 33 is reversible end-for-end and face-for-face; and to the fact that in each of these four positions it is shiftable radially. The face-for-face reversibility permits changing the plane in'which roller .42 operates, and this plane can be adjusted slightly further. by giving a slight S-bend to that end of arm 33 whichcarries the roller. The end-for-j end reversibility permits a considerable radial adjustability the axis of shaft 24, with possible.

In any given radial position, regardless of 'face-to-face abridge39. On each face plate 44 is provided with an open an inch. The range'is from With the block rotated 180? and the arm reversed end-.

for-end, the radial distance is equal to the graduation read by the upper end of theplate plus three-quarters of Without end-for-end reversibility, of from to 3" could not'have been obtained without shortening block 26 and plate 44, or lengthening arm 33.

Thus not only do the indentations and ridges cooperate to constitute part of the means for locking the-arm' in radial adjustment, but also theindentations serve as a graduated scale and the plate serves. as an'index for reading from this scale theetfective length ofthe arm. It will be seen that the present invention constitutes a new and useful calibrated, radially and angularly adjustable actuating lever for rotatable control shafts.

Now that one embodiment of the invention has been shown and described, it is to be understood that theinvention is not to be limited to the specific form or arrangement of parts herein shownand described.

' What is claimed is: a V .1. In a lever-actuated control. mechanismha'ving-a rotatable shaft, the combination'with said shaft, of a withthe shaft; means for securing the block for rotation block rigidly to the shaft; an actuating contact-arm carried by the block projecting therefrom radially with respect to f the shaft, and adjustable radially with respect thereto;

a clamp-plate overlying the face of the block; and means for'clamping the clamp-plate to'the block, to secure thearm rigidly between the plate and the block; wherein the block includes parallel guide-channels for the arm to slide in, and for preventing lateral movement of thearm with respect to the block; and wherein the block has a hole, in which the shaft is secured and through which the shaft projects beyond the face of the block;v and position, projections 43 on the face of block 26 engage radial distance from shaft center to roller center is equal to the graduation read by the upper edge of the plate plus an inchv nd alt. Qr alternatively said radial distance carrbe determined by. subtracting the graduation read by wherein the clamping means is ofiset from the shaft; and wherein the plate has an opening for engaging the projecting end of the shaft, thereby steadying the plate; and wherein the arm is bifurcated into two parallel branches,

which straddle the clamping means and the projecting end of the shaft. 7 7

2. Mechanism according'to claim 1; wherein there are evenly spaced indented transverse graduations on at least one face of both branches of the arm; and wherein there are cooperating transverse ridges on at least one of'the backs of the clamp plate and the face of the block, the distance between successive ridges being an integral multiple of the distance betweencorresponding successive indented graduations.

3. Mechanism according to claim 2; wherein the indented graduations are on and wherein the arm is reversible faCe-for-face; and having an actuating contact-roller journally mounted on one face of the'outer end of the arm.

4. Mechanism according toclaim 3; wherein the arm is reversible end-for-end.

References Cited in the file of this patent UNITED STATES PATENTS 128,306 Harvey June 25', 1872 144,217 Murgatroyd Nov, 4, 1873 273,276 ,Hawkinson Mar. 6, 1883 366,958 Holmgreen Q July 19, 1887 502,621 Fox Aug..1, 1893 1,799,261 Stoody Apr. 7, 1931 2,127,663 Hilkmeier Aug. :23, 1938 2,168,499 Spicacci Aug. 8, 1939 2,400,656 Schesser May 21, 1946. 2,602,350 Marcellus July 8, 1952 2,617,307

Drissner Nov. 11,

this combined range both faces of the arm; and wherein the ridges are on both the block and the plate; 

